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Effect of Air Circulation Velocity on the Rate of Lumber Drying in a Small Compartment Wood Drying Kiln (소형 목재인공건조실에 있어서 공기순환속도가 목재건조율에 미치는 영향)

  • Chung, Byung-Jae
    • Journal of the Korean Wood Science and Technology
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    • v.2 no.2
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    • pp.5-7
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    • 1974
  • 1. This study indicates that above the fiber saturation point the drying rate can be increased with increasing the velocity of the air circutation, i.e., the drying rate of sample boards is proportional to the air velocity, but below the fiber saturation point, the effect of the velocity of air circulation is very low as shown in Figs. 1 and 2. 2. Under the controlled temperature and humidity in the kiln, the more the sample boards have moisture, the higher drying rate of it can be obtained. In other words, this means that even though in the case of drying various moisture content of wood, at the final drying stage, approximately the same percentage of moisture content of wood can be secured by employing the higher velocity of air circulation. 3. This study shows that the rate of drying in kiln changes distinctly at the fiber saturation point, i, e., above the fiber saturation point, the drying curve shows concave aginst the X axsis, but below the fiber saturation point, in the range from 30 percent of moisture content to 20 percent of moisture content, the curve shows convex as shown in Fig. 3. As the drying progresses, however, the drying curve shows concave again below 20 percent of moisture content. This means that inflection point of drying curve may be located clearly at the fiber saturation point, i.e., 30 percent of moisture content. As mentioned above, the 30 percent of moisture content of wood at which the inflectional point appears can be recognized as a critical point, i. e., the fiber saturation point at which all free water was removed from wood. The existence of inflectional point indicates that the evaporation of hygroscopic water in a cell wall is more difficult than the evaporation of free water in a cell cavity and the minor space of cell wall. The convex curve in the range of moisture content from 30 percent to 20 percent means that the evaporation of capillary condensed water has a tendency of the same rates of drying approximately, but as approaching to the 20 percent of moisture, the transfusion of moisture from wood becomes difficult because of having less moisture in cell wall. Below 20 percent of moisture content, the drying curve shows concave again, which means that it is difficult to remove the moisture located nearer to the surface of cellulose molecules and the surface bound water. These relations were revealed in Fig. 4. In comparison AC curve which does not have the two inflection points with BD curve which has two inflection points, i.e., Band D, they are mentioned already, by existence of the inflection points, the curve BD shows that the change of drying rate in the interval from 20 percent of moisture content to 30 percent of moisture content is not greater than in the case of the curve AC in the same interval. At the inflection point of 30 percent of moisture content, it can be noticed that the changing of the drying rate is very conspicuous. This phenomenon also can be recognized, as it is noticed by the Fig. 3, the drying rate from green to 30 percent of moisture content is very great. But the inclination of the curve is very slow from 30 percent of moisture content to 20 percent of moisture content, i.e., the inclination of the curve becomes almost horizontal lines. Acknowledgments Gratitude is expressed to Fred E. Dickinson, Professor of 'Wood Technology, School of Natural Resources, University of Michigan, USA for his suggestion to carry out this study.

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A Study on Determination of Consumptive Use Needed in the Vegetable Plots for the Prevention of Drought Damage (고등채소의 한해를 방지하기 위한 포장 용수량 결정에 관한연구)

  • 최예환
    • Magazine of the Korean Society of Agricultural Engineers
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    • v.15 no.2
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    • pp.2949-2967
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    • 1973
  • The purpose of this study is to find out and determine the minimum consumptive use of water for Korean cabbage and turmp, so that the minimum water requirement can be secured always for a stable cultivation of these vegetables regardless of weather conditions. The experiment was conducted in two periods; first one from May to July and second one from August to October, each experiment with two varieties of cabbage and two varieties of radish with 2 replicants and 15 treatments. The results found from the above are briefly as follows: 1. Since the mean soil moisture equivalent 64 days after the treatment was 28.5% and the soil moisture content at the time was 2.67% which is far less than that of the wilting point, the crop seemed to be extremely caused by a drought. 2. The rate of 51 days after the seeding, soil moisture content of plot No.2 where irrigation has been continuous was the highest or 21.3%, whereas the plot No.14 without irrigations was 11.2% and the lowest. Therefore, the soil moisture content for the minimum qrowth seemed to be 20%. 3. The consumptive coefficient of Blaney and Criddle on cabbage in two periods were K=1.14 and 0.97 respectively, and on radish in two periods were K=1.06 and 0.86 respectively, thus, cabbage was higher than radish. The consumptive coefficient in the first experiment (May-July) was 0.17 to 0.20 higher than the 2nd experiment(August-October). 4. Nomally, cabbage and radish germinate within one week, however, the germination ot these crops which were treated with a suspended water supply from the beginning took two full weeks. 5. When it elapsed 30 days after seeding, the conditions in plot 1,2 and 3 were fairly good however, the crops in the plops other than these showed a withering and the leaves were withered and changed into high green due to an extrem drought. Though it was about same at the beginning, the drought damage on cabbage was worse than that on radish period, and the reasos for this appears in the latter that the roots are grown too deep. 6. The cabbage showed a high affinity between treated plots and varieties. Consequently, it can be said that cabbage is very suseptive to drought damage, and the yield showed a difference of 35% to 56% depending on the selection oe varieties. 7. The radish also showed a high affinity between the treated plots, however, almost us affinity existed between varieties. Therfore, the yield of radish largely depends on the extent of drought, and the selection of variety does not affect at all. 8. The normal consumptive use on cabbage is $0.62{\ell}/sec$, while that on radish is $0.64{\ell}/sec$, and the minimum optimum water requirement that was obtained in this study is $4,000cc/day/m^3$ or $0.462{\ell}/sec/ha$.

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Studies on the Chilling Injury of Rice seedlings. 1. Characterization of Chilling Injury & Recovery Different Leaf Stages (수도의 유초기 냉해에 관한 연구 1. 유묘기 엽령별 냉해발현 및 회복양태)

  • Kwon, Y.W.; Kim, J.H.;Ahn, S.B.
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.24 no.1
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    • pp.11-24
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    • 1979
  • To characterize elastic and plastic chilling injury, rice seedlings grown at 28/$16^{\circ}C$ day/night temp. under 20K lux (13hrs.) in a phytotron were subjected to a 11/$6^{\circ}C$, 20K lux condition for 2, 4, 6 or 8 days at 1, 2, 3, 4 or 5th leaf-stage, respectively, followed by further growth under 28/$16^{\circ}C$condition till 30th day after seeding. Japonica variety Jinheung and Chulwon No.1 survived almost 100% without any significant , discoloration and death of leaves due to chilling even under the chilling of 8 days at all seedling ages tested. Tongil and Yushin, varieties from Indica x Japonica cross, showed increasing discoloration of leaves and death of plants with increase in chilling intensity. The longest chilling duration shown seedling death less than 5% was 4, 6, 1, 4, 8 days for Tongil, and 6, 6, 1, 2, 2, days for Yushin at 1, 2, 3, 5th leaf-stage, respectively. The degree of discoloration and death of leaves or suppression of height growth was not explicitly related to seedling death or the dry weight reduction. The degree of seedling death or dry weight reduction could differentiate chilling tolerance of varieties and seedling ages, but somewhat differently. Reduction in dry weight due to chilling occurred even without any visible injury or seedling death. These suggest that both the degree of seedling death and reduction in dry weight should be considered in the test of varieties for chilling tolerance. Combined evaluation of seedling death and dry weight reduction indicated the most susceptible seedling age to chilling injury to be 1 to 2nd leaf-stage for Jinheung, 2 to 3rd leaf-stage for Chulwon No.1, 3rd leaf- stage for Tongil and Yushin, respectively.

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Prevalence of Drug-resistances in Patients with Pulmonary Tuberculosis and Its Association with Clinical Characteristics at One Tertiary Referral Hospital in Pusan, Korea (부산지역 한 3차 병원으로 내원한 폐결핵 환자에서 약제 내성률과 예측인자간의 연관성)

  • Son, Choon-Hee;Yang, Doo-Kyung;Rho, Mee-Sook;Jeong, Jin-Sook;Lee, Hyuck;Lee, Ki-Nam;Choi, Pil-Jo;Lee, Soo-Keol;Chang, Kwang-Yul;Choi, Ik-Soo
    • Tuberculosis and Respiratory Diseases
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    • v.51 no.5
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    • pp.416-425
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    • 2001
  • Background : The incidence of drug-resistant tuberculosis has recently decreased in Korea. However, it is still one of the major obstacles in treating pulmonary tuberculosis. This study was performed to determine the prevalence and clinical characteristics associated with drug-resistance in pulmonary tuberculosis at the tertiary referral hospital in Pusan, Korea. Methods : The medical records of 138 patients, who had been diagnosed as active pulmonary tuberculosis were retrospectively reviewed, and results of drug susceptibility from May 1997 to June 2000. The relationships among those with a history of previous tuberculosis treatment, the extent of lung involvement, the presence of cavities on the initial chest X-ray films and patterns of drug resistance were analyzed. Results : The total number of patients who had drug resistance to at least one drug was 55(39.9%). Among them 34(24.6%) had resistance to isoniazid(INH) and rifampin(RFP). There was drug resistance in 20(22%) of 91 patients without previous tuberculosis therapy, and among them 9(9.9%) were multi-drug resistant. Thirty-two(74.5%) out of 47 patients with previous therapy were drug-resistant and 25(53.2%) were multidrug resistant. For all 138 patients, resistance to INH was the most common(34.1%), followed by RFP(26.1%) and ethambutol(EMB)(14.5%). Drug resistance to INH, RFP, PZA and streptomycin(SM) were independently associated with a history of previous treatment(odds ratio; 9.43, 9.09, 8.93 and 21.6 respectively, p<0.01). The extent of lung involvement on the chest films was significantly associated with the drug resistance to INH and RFP(odds ratio; 2.12 and 2.40 respectively, p<0.01). The prevalence of drug resistance to RFP, INH and RFP was significantly more common in patients with a cavitary lesion on the chest films by multivariate analysis(odds ratio; 4.17 and 4.81 respectively, p<0.05). Conclusion : This study revealed that patients with a prior treatment history for pulmonary tuberculosis, and the presence of a cavitary lesion on chest films had a higher prevalence of anti-tuberculosis drug resistance. A very careful clinical and microbiological examination is needed for patients with such characteristics.

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Prospective Study of the Immunologic Factors Affecting the Prognosis of Severe Community-Acquired Pneumonia (중증 지역사회획득 폐렴환자의 예후에 영향을 미치는 면역지표에 대한 연구)

  • Hwang, Jae-Kyung;Lee, Ho-Moeng;Song, Kwang-Sik;Park, Gye-Young;Park, Jeong-Woong;Park, Jae-Kyung;Jeong, Seong-Hwan;Ahn, Jeong-Yeal;Seo, Yiel-Hea;Nam, Gui-Hyun
    • Tuberculosis and Respiratory Diseases
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    • v.50 no.4
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    • pp.437-449
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    • 2001
  • Background : In the severe community-acquired pneumonia, it has been known that the immune status is occasionally suppressed. This study was performed to identify the immunologic markers related with the prognostic factors in severe community-acquired pneumonia. Methods : 23 patients with severe community-acquired pneumonia were involved in this study, and divided into survivor (16) and nonsurvivor (7) groups. In this study, the medical history, laboratory tests(complete blood counts, routine chemistry profile, immunoglobulins, complements, lymphocyte subsets, cytokines, sputum and blood culture, urine analysis), and chest radiographs were scrutinized. Results : 1) Both groups had lymphopenia(total lymphocyte count $995.6{\pm}505.7/mm^3$ in the survivor and $624.0{\pm}287.6/mm^3$ in the nonsurvivor group). 2) The T-lymphocyte count of the nonsurvivor group($295.9{\pm}203.0/mm^3$) was lower than the survivor group($723.6{\pm}406.5/mm^3$) (p<0.05). 3) The total serum protein(albumin) was $6.0{\pm}1.0(2.7{\pm}0.7)\;g/d{\ell}$ in the survivor and $5.2{\pm}1.5(2.3{\pm}0.8)g/d{\ell}$ in the nonsurvivor group. The BUN of the nonsurvivor group($41.7{\pm}30.0mg/d{\ell}$) was higher than that of the survivor group($18.9{\pm}9.8mg/d{\ell}$)(p<0.05). The creatinine concentration was higher in the nonsurvivor group($1.8{\pm}1.0mg/d{\ell}$) than that in the survivor group($1.0{\pm}0.3mg/d{\ell}$)(p<0.05). 4) The immunoglobulin G level was higher in the survivor group($1433.0{\pm}729.5mg/d{\ell}$) than in the nonsurvivor group($849.1{\pm}373.1mg/d{\ell}$) (p<0.05). 5) The complement $C_3$ level was $108.0{\pm}37.9mg/d{\ell}$ in the survivor group and $88.0{\pm}32.1mg/d{\ell}$ in the nonsurvivor group. 6) A cytokine study showed an insignificant difference in both groups. 7) Chronic liver disease, DM, and COPD were major underlying diseases in both groups. Conclusion : These results suggest that decreased a T-lymphocyte count and immunoglobulin G level, and an increased BUN and creatinine level may be associated with the poor prognosis of severe community-acquired pneumonia.

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Clinical Manifestations of the Lung Involvement in Behçet's Syndrome (Behçet 증후군에서 폐침범의 임상양상에 관한 고찰)

  • Park, Kwang Joo;Park, Seung Ho;Kim, Sang Jin;Kim, Hyung Jung;Chang, Joon;Ahn, Chul Min;Kim, Sung Kyu;Lee, Won Young
    • Tuberculosis and Respiratory Diseases
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    • v.43 no.5
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    • pp.763-773
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    • 1996
  • Background : Behçet's syndrome is a chronic multisystemic disease affecting many organs such as skin, mucosa, eye, joint, central nervous system and blood vessels. Lung involvement occurs in 5% of Behçet's syndrome and is thought to be due to the pulmonary vasculitis leading to thromboembolism, aneurysm and arteriobronchial fistula. Pulmonary vasculitis in Behçet's syndrome is a unique clinical feature, differing from other vasculitis affecting the lung and is one of the major causes of death. Therefore, we examined the incidence, the clinical features, the radioloic findings and the clinical courses of the lung involvement in Behçet's syndrome. Methods: We retrospectively reviewed the medical records and radiologic studies of 10 cases of the lung involvement in Behçet's syndrome diagnosed at Yongdong Severance Hospital and Severance Hospital from 1986 to 1995. We analysed the clinical features, the radiological findings, the treatment modalities and the clinical courses. Results: 1) The incidence of the lung involvement in Behçet's syndrome was 2%(10/487). The male to female ratio was 8 : 2 and the mean age was 34 years. The presenting symptom was hemoptysis in 5 of 10 cases, and massive hemoptysis was noted in 2 cases. Other pulmonary symptoms were cough(6/10), dyspnea(4/10), and chest pain(2/10). Other manifestations were oral ulcers(10/10), genital ulcers(9/10), skin lesions(7/10), and eye lesions(6/10). 2) The laboratory findings were nonspecific. The posteroanterior views of chest radiographies showed multiple infiltrates(6/10), nodular or mass-like opacities(4/10), or normal findings(2/10). The chest CT scans showed multifocal consolidations(6/8), and aneurysms of the pulmonary aneries(4/8). The pulmonary angiographies were performed in 3 cases, and showed pulmonary artery aneurysms in 2 cases. The ventilation-perfusion scans in 2 cases of normal chest x-ray showed multiple mismatched findings. 3) The patients were treated with combination therapy consisting of corticosteroids, cyclophosphamide, and colchicine or anticoagulant agents. Surgical resection was performed in one case with a huge aneurysm. 4) We have followed up nine of ten cases. Three cases are well-being with medical therapy, two cases are severely disabled now and four cases died due to massive hemoptysis, massive pulmonary embolism, or sepsis. Conclusion : Pulmonary vasculitis is a main feature of the lung involvement of Behçet's syndrome, causing hemorrhage, aneurysmal formation, and/or thromboemboism. The lung involvement of Behçet's syndrome is uncommon but is one of the most serious prognostic factors of the disease. Therefore, an aggressive diagnostic work-up for early detection and proper treatment are recommended to improve the clinical course and the survival.

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The Clinical Features of Endobronchial Tuberculosis - A Retrospective Study on 201 Patients for 6 years (기관지결핵의 임상상-201예에 대한 후향적 고찰)

  • Lee, Jae Young;Kim, Chung Mi;Moon, Doo Seop;Lee, Chang Wha;Lee, Kyung Sang;Yang, Suck Chul;Yoon, Ho Joo;Shin, Dong Ho;Park, Sung Soo;Lee, Jung Hee
    • Tuberculosis and Respiratory Diseases
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    • v.43 no.5
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    • pp.671-682
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    • 1996
  • Background : Endobronchial tuberculosis is definded as tuberculous infection of the tracheobronchial tree with microbiological and histopathological evidence. Endobronchial tuberculosis has clinical significance due to its sequela of cicatrical stenosis which causes atelectasis, dyspnea and secondary pneumonia and may mimic bronchial asthma and pulmanary malignancy. Method : The authors carried out, retrospectively, a clinical study on 201 patients confirmed with endobronchial tuberculosis who visited the Department of Pulmonary Medicine at Hangyang University Hospital from January 1990 10 April 1996. The following results were obtained. Results: 1) Total 201 parients(l9.5%) were confirmed as endobronchial tuberculosis among 1031 patients who had been undergone flexible bronchofiberscopic examination. The number of male patients were 55 and that of female patients were 146. and the male to female ratio was 1 : 2.7. 2) The age distribution were as follows: there were 61(30.3%) cases in the third decade, 40 cases(19.9%) in the fourth decade, 27 cases(13.4%) in the sixth decade, 21 cases(10.4%) in the fifth decade, 19 cases(9.5%) in the age group between 15 and 19 years, 19 cases(9.5%) in the seventh decade, and 14 cases(7.0%) over 70 years, in decreasing order. 3) The most common symptom, in 192 cases, was cough 74.5%, followed by sputum 55.2%, dyspnea 28.6%, chest discomfort 19.8%, fever 17.2%, hemoptysis 11.5%, in decreasing order, and localized wheezing was heard in 15.6%. 4) In chest X-ray of 189 cases, consolidation was the most frequent finding in 67.7%, followed by collapse 43.9%. cavitary lesion 11.6%, pleural effusion 7.4%, in decreasing order, and there was no abnormal findings in 3.2%. 5) In the 76 pulmanary function tests, a normal pattern was found in 44.7%, restrictive pattern in 39.5 %, obstructive pattern in 11.8%, and combined pattern in 3.9%. 6) Among total 201 patients, bronchoscopy showed caseous pseudomembrane in 70 cases(34.8%), mucosal erythema and edema in 54 cases(26.9%), hyperplastic lesion in 52 cases(25.9%), fibrous s.enosis in 22 cases(10.9%), and erosion or ulcer in 3 cases(1.5%). 7) In total 201 cases, bronchial washing AFB stain was positive in 103 cases(51.2%), bronchial washing culture for tuberculous bacilli in 55 cases(27.4%). In the 99 bronchoscopic biopsies, AFB slain positive in 36.4%. granuloma without AFB stain positive in 13.1%, chronic inflammation only in 36.4%. and non diagnostic biopsy finding in 14.1%. Conclusions : Young female patients, whose cough resistant to genenal antitussive agents, should be evaluated for endobronchial tuberculosis, even with clear chest roentgenogram and negative sputum AFB stain. Furthermore, we would like to emphasize that the bronchoscopic approach is a substantially useful means of making a differential diagnosis of atelectasis in older patients of cancer age. At this time we have to make a standard endoscopic classification of endobronchial tuberculosis, and well designed prospective studies are required to elucidate the effect of combination therapy using antituberculous chemotherapy with steroids on bronchial stenosis in patients with endobronchial tuberculosis.

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Dietary Habits, Body Weight Satisfaction and Eating Disorders according to the Body Mass Index of Female University Students in Kyungnam Province (경남 지역 일부 여대생의 비만도에 따른 식습관, 체중 만족도 및 섭식 장애에 관한 연구)

  • Park, Kyung-Ae
    • Journal of the East Asian Society of Dietary Life
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    • v.19 no.6
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    • pp.891-908
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    • 2009
  • This study was performed to investigate the dietary habits, body weight satisfaction and eating disorder tendencies of female university students in Kyungnam province. Anthropometric measurements, dietary habits, body weight satisfaction, food preferences, disordered eating, and nutrient intakes were assessed in 132 female students at Kaya University. The results were analyzed with $x^2$- and ANOVA tests using the SPSS package program. The average age of the subjects was 20.1 years and average body mass index (BMI) were $21.1\;kg/m^2$. According to BMI, the percentages of students who were underweight, normal weight and overweight by BMI were 21.2, 55.3, and 23.5, respectively. Duration of exercise was significantly different by BMI. Index scores for a mini dietary assessment were significantly higher in the normal and overweight groups than in the underweight group. Scores for sweet, salty, and meat preferences were highest and scores for bean and vegetable preferences were lowest, in the underweight group. Satisfaction for present body weight was lowest, and self-perception of body image and weight control experiences were highest in the overweight group. All subjects in the overweight group wanted to be slim, and those in the normal and underweight groups, preferred to be more slim despite their current body weight being in the normal or below normal range. The percentage of the subjects who were at risk for eating disorders (based on scores from the Eating Attitude Test-26, EAT-$26{\geqq}20$) was 11.3%. Scores for EAT-26 were higher in the overweight group than in the underweight and normal weight groups. Nutrient intakes were not different among the groups. Therefore, dietary habits, taste and food preferences, satisfaction for present body weight, and disordered eating were significantly different according to BMI. These results suggest that overweight female university students need help correcting disordered eating, and nutrition counseling should be established to aid desirable weight control methods. Those who are underweight and normal weight need help establishing proper perceptions of their normal body weight and body image as well as nutrition counseling for health.

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Removal of Red Tide Organisms -2. Flocculation of Red Tide Organisms by Using Loess- (적조생물의 구제 -2. 황토에 의한 적조생물의 응집제거-)

  • KIM Sung-Jae
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.33 no.5
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    • pp.455-462
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    • 2000
  • The objective of this study was to examine the physicochemical characteristics of coagulation reaction between loess and red tide organisms (RTO) and its feasibility, in developing a technology for the removal of RTO bloom in coastal sea. The physicochemical characteristics of loess were examined for a particle size distribution, surface characteristics by scanning electron microscope, zeta potential, and alkalinity and pH variations in sea water. Two kinds of RTO that were used in this study, Cylindrothen closterium and Skeietonema costatum, were sampled in Masan bay and were cultured in laboratory. Coagulation experiments were conducted using various concentrations of loess, RTO, and a jar tester. The supernatant and RTO culture solution were analyzed for pH, alkalinity, RTO cell number. A negative zeta potential of loess increased with increasing pH at $10^(-3)M$ NaCl solution and had -71.3 mV at pH 9.36. Loess had a positive zeta potential of +1,8 mV at pH 1.98, which resulted in a characteristic of material having an amphoteric surface charge. In NaCl and $CaCl_2$, solutions, loess had a decreasing negative zeta potential with increasing $Na^+\;and\;Ca^(+2)$ ion concentration and then didn't result in a charge reversal due to not occurring specific adsorption for $Na^+$ ion while resulted in a charge reversal due to occurring specific adsorption for $Ca^(+2)$ ion. In sea water, loess and RTO showed the similar zeta potential values of -112,1 and -9.2 mV, respectively and sea sand powder showed the highest zeta potential value of -25.7 mV in the clays. EDLs (electrical double-layers) of loess and RTO were extremely compressed due to high concentration of salts included in sea water, As a result, there didn't almost exist EDL repulsive force between loess and RTO approaching each other and then LVDW (London-yan der Waals) attractive force was always larger than EDL repulsive force to easily form a floe. Removal rates of RTO exponentially increased with increasing a loess concentration. The removal rates steeply increased until $800 mg/l$ of loess, and reached $100{\%}$ at 6,400 mg/l of loess. Removal rates of RTO exponentially increased with increasing a G-value. This indicated that mixing (i.e., collision among particles) was very important for a coagulation reaction. Loess showed the highest RTO removal rates in the clays.

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The Radioprotective Effect and Mechanism of Captopril on Radiation Induced-Heart Damage in Rats (방사선 조사 후 발생한 흰쥐 심장손상에서 Captopril의 방어역할과 기전)

  • Chang Seung-Hee;Lee Kyung-Ja;Koo Heasoo
    • Radiation Oncology Journal
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    • v.22 no.1
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    • pp.40-54
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    • 2004
  • Purpose : Captopril (angiotension converting enzyme inhibitor) is known to have a radioproptective effect in the lungs, intestines and skin, but its effect in the heart is unclear. To investigate the radioprotectlve efiect and mechanism of captopril on the heart, the histopathological changes and immunohistochemical stains were compared with radiation alone, and radiation combined with captopril, in the rats. Materials and Methods : The histopathological changes and immunohistochemical stains ($TNF{\alpha}$, $TGF{\beta}1$, PDGF and FGF2) were examined in the radiation alone and the combined captopril and radiation groups, 2 and 8 weeks after irradiation. Each group consisted of 8 to 10 rats (Sprague-Dawley). Irradiation (12.5 Gy) was given to the left hemithorax in a single fraction. Captopril (50 mg/Kg/d) mixed with water, was given orally and continuously from the first week prior to, up to the 8th week of the experiment. Results : In the radiation alone group, the ventricle at 2 weeks after irradiation showed prominent edema (p=0.082) and fibrin deposit (p=0.018) compared to the control group. At 8 weeks, the edema was decreased and fibrosis increased compared to those at 2 weeks. The histopathological changes of the combined group were similar to those of the control group, due to the reduced radiation toxicity at 2 and 8 weeks. The endocardial fibrin deposit (p=0.047) in the atrium, and the interstitial fibrin deposit (p=0.019) and edema (p=0.042) of the ventricle were reduced significantly in the combined group compared to those in the radiation alone group at 2 weeks. The expressions of $TNF-{\alpha}$, $TGF-{\beta}1$, PDGF and FGF-2 in the radiation alone group were more increased than in the control group, especially in the pericardium and endocardium of the atrium at 2 weeks. At 8 weeks, the pericardial $TNF-{\alpha}$ and $TGF-{\beta}1$ in the radiation alone group continuously increased. The expressions of $TNF-{\alpha}$, $TGF-{\beta}1$ and PDGF were decreased in the combined group at 2 weeks. At 8 weeks, the expressions of $TNF-{\alpha}$ in the atrial and ventricular pericardia were markedly reduced (p=0.049, p=0.009). Conclusion : This study revealed that the early heart damage induced by radiation can be reduced by the addition of captopril in a rat model. The expressions of $TNF-{\alpha}$, $TGF-{\beta}1$ and PDGF were further decreased in the combined compared to the radiation alone group at both 2 and 8 weeks. From these results, it may be concluded that these cytokines probably play roles in the radioprotective mechanism of captopril from the radiation-induced heart toxicity, similarly to in other organs.